package com.alphaking.servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

public class Check_Code extends HttpServlet{

	private Font myFont = new Font("Arial Black", Font.PLAIN, 16);


	Color getRandColor(int fc, int bc) {
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	@Override
	public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		response.setHeader("Cache-Control", "no-cache");
		response.setContentType("image/jpeg");

		
		int width = 80, height = 20;

		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

		Graphics g = image.getGraphics();
		Random random = new Random();
		g.setColor(getRandColor(200, 250));
		g.fillRect(1, 1, width - 1, height - 1);
		g.setColor(new Color(102, 102, 102));
		g.drawRect(0, 0, width - 1, height - 1);
		g.setFont(myFont);

		g.setColor(getRandColor(160, 200));

		String sRand = "";
		for (int i = 0; i < 4; i++) {

			String tmp = getRandomChar();
			sRand += tmp;

			g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
			g.drawString(tmp, 15 * i + 10, 15);
		}

		HttpSession session = request.getSession(true);
		session.setAttribute("rand", sRand);
		g.dispose();
		ImageIO.write(image, "JPEG", response.getOutputStream());

	}

	private String getRandomChar() {

	
		int rand = (int) Math.round(Math.random() * 2);
		long itmp = 0;
		char ctmp;

		switch (rand) {

		case 1:
			itmp = Math.round(Math.random() * 25 + 65);
			ctmp = (char) itmp;
			return String.valueOf(ctmp);

		case 2:
			itmp = Math.round(Math.random() * 25 + 97);
			ctmp = (char) itmp;
			return String.valueOf(ctmp);

		default:
			itmp = Math.round(Math.random() * 9);
			return String.valueOf(itmp);
		}
	}
}
